In situ observations of fundamental characteristics of the Sun and astrophysical plasmas
Abstract
This presentation will focus on in situ observations of the solar wind and how these data can be used to deduce key properties of the Sun and derive properties of plasmas in the solar atmosphere and wind. First we will focus on novel measurements of the elemental composition in the solar wind, and discuss the constraints thy place on the solar metallicity, a measure of the Sun’s proportion of elements heavier than He, and their consequences for solar EUV and X-ray irradiance. The composition of the solar photosphere and upper atmosphere has been debated recently, mainly due to the results from novel inversion models applied to spectroscopic observations of the photosphere.The second part of the presentation will focus on the dynamic properties of solar wind in the atmosphere, especially the issue of energy distribution in plasmas among the components and field. We will first focus on some key results of ionic composition and their relation to the dynamic processes in the corona. Second, we will look at the distribution of energy among the ion components of these plasmas, reflecting both collisional effects and wave-particle interactions near the Sun and in the heliosphere.
- Publication:
-
IAU General Assembly
- Pub Date:
- August 2015
- Bibcode:
- 2015IAUGA..2255340Z